[H] SLi Benchmark Analysis

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coz

[H]ard|Gawd
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Using the [H] SLi benchmark numbers on the front page I looked at how much of a boost SLi was delivering. I also added in some made-up numbers for a possible 6900U/NV48 card running at 500MHz core just to annoy the fanATicz..... ;)

I based the increase in fps for 6900U on twice the boost between 6800GT and 6800U added to the 6800U score - hardly scientific I know so don't take the numbers as Gospel!! I based the SLi performance boost for 6900U on the diminishing improvement percentage between 6800GT and 6800U (eg. if the SLi % boost dropped 3% between 6800GT and 6800U then I'd make it 6% between 6800U and 6900U).

For anyone thinking my numbers are utter crap and I'm sitting here with rabid foam dripping from my lips then you're probably right but take the scores for what they're worth (not much) and don't take them seriously......

Test Config.
DOOM3 - 1600x1200,32-bit, 4XAA
Halo - 1600x1200, 32-bit, NoAA
3DMark05 - 1024x768 Default
Athlon 64 4000+ 1GBDDR400, ASUS nForce4 SLI

SLi-benchies.PNG


But for the actual [H] numbers for 6600GT/6800GT and 6800U it shows SLi is delivering some fairly decent performance gains. It's hard to tell if the game itself favours SLi or the particular resolution+AA setting but Doom3 and 3DMark05 show the best SLi boost - around 70-85%, not too shabby at all. Halo shows pretty poor gains but it could be CPU-limited.

Anyway, SLi is looking pretty decent so far - looks like my Spring refresh upgrade will involve the selling of my last remaining kidney. Oh well, there's always dialysis!! :D
 
im still wondering how sli = %95 when the mobos are all 16x and 8x, how can you get more thanb 50% out of that 8x slot?!
 
I thought it was "up to" 85%?

And is it possible that some of the data stream gets piped over the SLI bridge to compensate for the smaller PCI-E slot?
 
Or why would anyone believe a score with no information around what was used and on yet to be released hardware........
 
That's what I was thinking originally. This is all a bunch of horse shit. Just more palm greasing for the masses...
 
Wolf-R1 said:
I thought it was "up to" 85%?

And is it possible that some of the data stream gets piped over the SLI bridge to compensate for the smaller PCI-E slot?
Click to expand...

thats my point...i have yet to see a definitive tech article on using SLI with current or near current motherboards...why bother? how does it work? do they share channels? if you share the 16x, does the card on 16x lose performance? does 16x + 8x = 2*(12x) channels? or does the 16x channel have so much banddwith available, it can share? if so, why do the single SLI cards not perform any better?

i just fail to see the point, thats all
 
No current game makes ful usage of PCI-E's 16x.
Not even AGP 8x is fully utilised in modern games.


Terra - My rig wil feature SLI, sorry ATI, my money goes to nVidia next time :)
 
Steel Chicken said:
im still wondering how sli = %95 when the mobos are all 16x and 8x, how can you get more thanb 50% out of that 8x slot?!
Click to expand...

There will be plenty of bandwidth spare even on that 8x slot.

The loss of efficiency comes in the extra work and communication which has to be done to put together the two parts of the frame. However, the real reason you won't often see close to a 100% speed increase is CPU limitation. A frame can't be drawn until both the CPU and the video card have finished doing what they have to do to produce the frame. With this much video power games are likely to be CPU limited for the majority of the play time, except at the highest resolutions with AA/AF enabled.

These performance increases are nice, but don't expect to see nearly as much increase at the lower resolutions, or without AA/AF. The 6800GT / U SLI setup seems quite hard to justify unless you're planning on playing games at 1600*1200 with 4xAA, and you have a very good CPU.
 
ok, that makes a little more sense then.
so, we need more SMP systems out there, Dual Cores, and game developers need to spend more time with multi-threading their apps
 
Terra said:
Terra - My rig wil feature SLI, sorry ATI, my money goes to nVidia next time :)
Click to expand...
What if it won't cost $1000.00 in video cards, a 600 watt power supply, and air conditioning to get the same performance with ATI? ;)
 
R1ckCa1n said:
What if it won't cost $1000.00 in video cards, a 600 watt power supply, and air conditioning to get the same performance with ATI? ;)
Click to expand...

Where is youre proof on that?
where is ati's call for SLI? last i saw ati had shit to compete against SLI..so stop making stupid ass asumptions
 
Arseface said:
These performance increases are nice, but don't expect to see nearly as much increase at the lower resolutions, or without AA/AF. The 6800GT / U SLI setup seems quite hard to justify unless you're planning on playing games at 1600*1200 with 4xAA, and you have a very good CPU.
Click to expand...
That's right, I think situations where fill-rate is the major bottleneck will see most benefit. But then you'd hardly spend that kind of money on an SLi setup if you're playing your games at 1024x768 or without AA etc.

I think 70-80% increased performance is worth the extra cost over a single card setup but that's my opinion and I don't expect everyone to share it. :)
 
I for one wholeheartedly agree. Really tired of people who think they'll never afford the system or are stupidly loyal to one brand trying to act like that somehow makes sli a piece of junk.
 
R1ckCa1n said:
What if it won't cost $1000.00 in video cards, a 600 watt power supply, and air conditioning to get the same performance with ATI?
Click to expand...
Wow!! Sounds great, all the SLi performance and only half the fat!!

Which ATi product is this you're talking about? :)
 
Steel Chicken said:
im still wondering how sli = %95 when the mobos are all 16x and 8x, how can you get more thanb 50% out of that 8x slot?!
Click to expand...

16x PCIe = 16 lane highway
8x PCIe = 8 lane highway

Texture data + geometry data + vertex data = cars on the highway

speed of GPU = speed limit on the highway

There are not enough cars on the higway to fill up the 8 lane highway much less the 16 lane highway, so the current limit of how traffic flows is the speed limit on the highway, not how many lanes are available.

This is why you can run a 6800U on a AGP4x (4 lane highway) slot and not loose more than a few % in performance. But if you narrow the highway enough (1x agp slot) than no matter what the speed limit is, you will not get as much traffic through (fps) in a given time as a larger highway.

==>Lazn
 
Steel Chicken said:
thats my point...i have yet to see a definitive tech article on using SLI with current or near current motherboards...why bother? how does it work? do they share channels? if you share the 16x, does the card on 16x lose performance? does 16x + 8x = 2*(12x) channels? or does the 16x channel have so much banddwith available, it can share? if so, why do the single SLI cards not perform any better?

i just fail to see the point, thats all
Click to expand...

There was supposed to be a point? Hmm...

In that case it would be "Who can throw the most money away the quickest". :eek: :D
 
[RIP]Zeus said:
Where is youre proof on that?
where is ati's call for SLI? last i saw ati had shit to compete against SLI..so stop making stupid ass asumptions
Click to expand...



You forget who your speaking to man he sees noting but red and cant seem to grasp reality. Hes already been banned once if memory serves right and now hes back.
 
I dont think ati has to have an sli card, other than you increase their e-penis.
An SLI setup costs upwards of 800 dollers, how many guys you think will run them? ;)
 
Moloch said:
I dont think ati has to have an sli card, other than you increase their e-penis.
An SLI setup costs upwards of 800 dollers, how many guys you think will run them? ;)
Click to expand...

not the whole story if you ask me. i am convinced ATI indeed *has* to react to an SLI setup sooner or later - be it just for marketing reasons. it's no good being stomped in all benchmarks in articles read by average consumers - high-end cards always made sense, too, by making the masses buy the products of the 'king of the hill' IMHO.

and maybe ATI is working on it? "While we do not know for sure what "Kaleidoscope" is, ATI's comments about multiple VPU support may indicate that it has something to do with that technology. As for the new graphics core that comes with it, we know little." - Anandtech

edit: e-penis... rofl, that hits the nail on the head :D
 
[RIP]Zeus said:
Where is youre proof on that?
where is ati's call for SLI? last i saw ati had shit to compete against SLI..so stop making stupid ass asumptions
Click to expand...
So seeing benchmarks ran by nV is proof of how good their SLI is? Again, on an unreleased product..... You green boys sure can see the future clearly
 
How did they manage 5200 3dmark with a stock ultra? I get 5600 @450/1290!!!

Are they using beta drivers not yet released?
 
Moloch said:
I dont think ati has to have an sli card, other than you increase their e-penis.
An SLI setup costs upwards of 800 dollers, how many guys you think will run them? ;)
Click to expand...
800.00 for the cards only if you don't buy the high-end. That does not include the new motherboard, CPU, power supply, and 200 amp service to the house to power the monster.

how many will run it? If it is 3/4 of what nV claims, doesn't require running special paths for each game and doesn't create thermal meltdown inside a case, I will. ;)
 
For you people talking price, there is nothing that says you must buy both cards right away. If I buy a PCI-E motherboard and video card today, I can buy a second video card in a few months when prices drop. Tons of people did that with Voodoo2 and tons will do it again with this.

As far as ATI goes, maybe they do have an SLI offering coming soon or maybe even a dual GPU card. They have done it before.. However, with AMD and Intel talkin up dual-core chips these days, and them being the new rage, it wouldn't surprise me one bit to see a dual-core graphics chip come out. Maybe ATI has one up their sleeves?
 
R1ckCa1n said:
800.00 for the cards only if you don't buy the high-end. That does not include the new motherboard, CPU, power supply, and 200 amp service to the house to power the monster.
Click to expand...

cpu?
 
R1ckCa1n said:
What if it won't cost $1000.00 in video cards, a 600 watt power supply, and air conditioning to get the same performance with ATI? ;)
Click to expand...

Dreams are nice, reality is better :)
 
wizzackr said:
and maybe ATI is working on it? "While we do not know for sure what "Kaleidoscope" is, ATI's comments about multiple VPU support may indicate that it has something to do with that technology. As for the new graphics core that comes with it, we know little." - Anandtech
Click to expand...
Kaleidoscope is a next-gen IGP core (integrated graphics) due for release in Q1 '06, doesn't sound like a high-end performer to me.
 
tornadotsunamilife said:
cpu?
Click to expand...
Don't expect to see dual PCI-e boards for Athlon XP's and older P4's, so yes a CPU. Take a look at 95% of this board and you will see XP's and older / non LGA775 Intel's.
 
coz said:
Kaleidoscope is a next-gen IGP core (integrated graphics) due for release in Q1 '06, doesn't sound like a high-end performer to me.
Click to expand...
Sounds like huge OEM cash around the corner.
 
coz said:
Anyway, SLi is looking pretty decent so far - looks like my Spring refresh upgrade will involve the selling of my last remaining kidney. Oh well, there's always dialysis!! :D
Click to expand...


Hehehe...I remember the first time I was able to play Quake2 at 1024x768...I was a GOD


Yea, SLI is cool...but I will wait until the PCI-express boards are more available and prices go down.

(For you newbies: Voodoo2 SLI was the ONLY way to do it back then).
 
origionaly posted by -freon- "For you people talking price, there is nothing that says you must buy both cards right away. If I buy a PCI-E motherboard and video card today, I can buy a second video card in a few months when prices drop. Tons of people did that with Voodoo2 and tons will do it again with this."

Voodoo II's had no bios. And some, seemingly identical cards, bought several months apart, had issues with one another. I'm really skeptical about buying one card now, and then 6months, 3 board revisions, and 4 bios revisions later, buying another, seemingly identical card, even from the same manufacturer, and expecting it to work. Will wait and see on this one. I think I can get another year out of my current rig.
 
GORANKAR said:
origionaly posted by -freon- "For you people talking price, there is nothing that says you must buy both cards right away. If I buy a PCI-E motherboard and video card today, I can buy a second video card in a few months when prices drop. Tons of people did that with Voodoo2 and tons will do it again with this."

Voodoo II's had no bios. And some, seemingly identical cards, bought several months apart, had issues with one another. I'm really skeptical about buying one card now, and then 6months, 3 board revisions, and 4 bios revisions later, buying another, seemingly identical card, even from the same manufacturer, and expecting it to work. Will wait and see on this one. I think I can get another year out of my current rig.
Click to expand...

How much do you guys wanna bet a lot of manufacturers are gonna take this one step farther and sell two 6800's or 6600's in one box and called it an "SLI matched pair" just like they do with DDR with the hopes of suckering people into thinking that its the only way to do things. However, it would be pretty cool to open a box to find a pair of 6800U's.....even if it did cost over $900 USD. :rolleyes:
 
Damn i was hoping i could Hook Up 4 6800 Ultras LOL, but seriously i will be ready to dump the funds for SLI 6800Us, i was the first on the block with my Voodoos in SLI and i loved them, i cant wait im drolling now, and when i get them ill wipe my ass with my X800XT-PE card lol.
 
R1ckCa1n said:
800.00 for the cards only if you don't buy the high-end. That does not include the new motherboard, CPU, power supply, and 200 amp service to the house to power the monster.
Click to expand...
You could also argue that an LGA775 processor itself is extremely expensive because you have to buy a new motherboard and memory to go with it. But there's a lot of guys out there who are building new rigs and performing major upgrades and will be buying new video cards, CPUs, motherboards, PSUs anyway. In those situations the added cost of SLi is basically the extra card ($200-500), the SLi connector and a slightly more expensive PSU and motherboard than you were going to get anyway. If you were in that situation would you not even buy an SLi-capable motherboard to give you the option of going SLi at a later date? Seems like a no-brainer in those situations.
 
Marcdaddy said:
Damn i was hoping i could Hook Up 4 6800 Ultras LOL, but seriously i will be ready to dump the funds for SLI 6800Us, i was the first on the block with my Voodoos in SLI and i loved them, i cant wait im drolling now, and when i get them ill wipe my ass with my X800XT-PE card lol.
Click to expand...

Haha.....very nice. :cool:

The one thing I still want to know is how overclocking is going to work. The cards would technically have to be clocked the same you'd think....otherwise one'd be running faster and drawing "it's half" at a different speed. :p

Maybe Nvidia will just make it easy on us and incorporate an autodetect and clock testing that checks both cards in coolbits during the testing/detection and gives a result that both cards'll do.

I'm really tempted to drop any further system upgrades right now (3.2E/new ram) and just start saving like mad for a s939 nForce4 SLI setup.....seriously.....it's WAY to tempting.
 
Back in the voodoo II days there was a manufacturer, can't remember who. that made a slightly less expensive version of the card with out the extra rear connectors. It's only purpose in life was to be the second card in a SLI rig. Hopefully one of the 6800 makers will do something like that. Will save some people a few dollars.

Don't know if it's possible, but put two chips on one board Voodoo5 style. Buy yourself a 300 watt AT psu to power just vc's, and your good to go ;)
 
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